Live data from Hacker News

Energy-based model explains how chronic stress transforms into disease over time

sciencedirect.com

21–30 of 60 posts

Re: Energy-based model explains how chronic stress transforms into disease over time

#21

Earlier quoted context omitted.

Exercise seems to stimulate the mechanisms it’s claiming stress depresses, so probably no.

But exercise does use lots of energy. Probably more than stress.

The body tends to use the same amount of energy regardless of what you do in a day. You can certainly over exercise which causes undue stress on the body. However other than an adaptive period at the start of regular exercise your body adapts to the increased caloric use from exercise by down regulating other processes to conserve energy. Typically an excess of calories is used by production of lipid fluid in adipose tissue and over expression of global inflammation. Once you begin exercising regularly the body generally stops using stored lipids for extra energy to compensate for the exercise and instead down regulates inefficient and generally harmful processes like random global inflammation.

As mentioned the Goldilocks zones are where you’re not forcing the body beyond what it can safely allocate to exercise in a day without causing stress in other processes. Generally though that Goldilocks zone is significantly greater than most people do in exercise in a week, but would typically fall in the zone of “moderate” exercise from a clinical point of view. This is effectively 3-6 times the expenditure of energy from rest for 150 minutes per week spread over a week for at least 10 minutes of moderately strenuous exercise at 70% heart rate per session. Most people in their 40’s or 50’s would typically find this fairly grueling, but that’s because of that homeostatic adaptation - the body resists changing its homeostasis and induces all sorts of negative experiences during the adaptation phase. Once you’ve adapted the opposite feelings present for the same reason - you begin to crave a routine of exercise because you body resists the adaptation to a more sedentary life.

N.b., This is why while exercise definitely helps lose weight, it’s primarily by managing inflammation and mood. This is why the only significant way you can lose weight over time is to reduce caloric intake materially under your homeostatic energy consumption.

Re: Energy-based model explains how chronic stress transforms into disease over time

#22
post #13

This paper reminds me of the “insight” / factoid that all mammals are basically born with the same rough number of heartbeats, and then they die. Smaller animals like mice have shorter lifespans and faster heartbeats. Larger ones like whales and elephants have slower heartbeats and longer lives. The humorous (and obviously false, though apparently not if this paper is out there) corollary is that any exercise and non…

This is the battery “theory,” and is obviously untrue from all evidence collected. Exercise and specifically improvement of VO2max, which is the bodies ability to pump and process a volume of blood and oxygen in a period of time, are some of the strongest predictors of life and health span. A lack of exercise also transpires to significantly increase global inflammation in the body - in fact regular exercise forces t…

> This is the battery “theory,” and is obviously untrue from all evidence collected. Exercise and specifically improvement of VO2max, which is the bodies ability to pump and process a volume of blood and oxygen in a period of time, are some of the strongest predictors of life and health span.

Exercise and specifically improvement of VO2max also decrease your average heart rate, so it's quite aligned with the battery theory.

Re: Energy-based model explains how chronic stress transforms into disease over time

#23
post #12

it sounds like the authors are suggesting that additional energy usage caused by stress can, in isolation from other causes, be a mechanism for disease. But that doesn’t make much sense: - our metabolisms are adaptable, so why wouldn’t this increase in energy use simply be offset by an increase in energy production? It can’t be that people who are stressed in general aren’t getting enough energy, because that would c…

Humans have a massive capacity to vary energy use. Highly trained endurance athletes like professional road cyclists and triathletes can average 3x or more the typical daily energy expenditure of a non-athlete on a long term basis. The idea that psychological stress can overwhelm the body's ability to produce energy does not seem credible to me.

Re: Energy-based model explains how chronic stress transforms into disease over time

#24
post #13

This paper reminds me of the “insight” / factoid that all mammals are basically born with the same rough number of heartbeats, and then they die. Smaller animals like mice have shorter lifespans and faster heartbeats. Larger ones like whales and elephants have slower heartbeats and longer lives. The humorous (and obviously false, though apparently not if this paper is out there) corollary is that any exercise and non…

This is the battery “theory,” and is obviously untrue from all evidence collected. Exercise and specifically improvement of VO2max, which is the bodies ability to pump and process a volume of blood and oxygen in a period of time, are some of the strongest predictors of life and health span. A lack of exercise also transpires to significantly increase global inflammation in the body - in fact regular exercise forces t…

OG study that found a roughly same number of heartbeats was only concerned with averages - https://pubmed.ncbi.nlm.nih.gov/9316546/ . Interestingly humans are outliers with 2-3x the expected number of heartbeats. The way the data was presented always gave me a strong "everything looks linear when plotted on a log scale with big marker" vibe... however it could be totally possible that there is some correlation there.

Maybe evolutionary, there is optimal amount of time for organisms to survive relative to their size. Organism size, in turn, correlates with heart size and heart size correlates with how fast it beats. Probably totally missing the mark, but if it was true, it would be interesting to look into why there are outliers.

Anywho, I find it humorous to think about a battery theory car analogy - "every car has a preset number of miles and maintenance would decrease usable lifespan of the car because you need to drive to the mechanic".

Re: Energy-based model explains how chronic stress transforms into disease over time

#25

Earlier quoted context omitted.

But exercise does use lots of energy. Probably more than stress.

The body tends to use the same amount of energy regardless of what you do in a day. You can certainly over exercise which causes undue stress on the body. However other than an adaptive period at the start of regular exercise your body adapts to the increased caloric use from exercise by down regulating other processes to conserve energy. Typically an excess of calories is used by production of lipid fluid in adipose…

How did you come by this information and do you have any sources / further reading on this?

Re: Energy-based model explains how chronic stress transforms into disease over time

#26
post #13

This paper reminds me of the “insight” / factoid that all mammals are basically born with the same rough number of heartbeats, and then they die. Smaller animals like mice have shorter lifespans and faster heartbeats. Larger ones like whales and elephants have slower heartbeats and longer lives. The humorous (and obviously false, though apparently not if this paper is out there) corollary is that any exercise and non…

Haven't done the math but maybe they aren't so disconnected. If I can trade off an elevated heart rate of 170 for an hour every day or two in exchange for dropping my resting heartbeat from 70 to 50, I should end up with more years to use those finite heartbeats. As with most things in life it's about balance. Extremes and absolutes in most everything tend to result in poor outcomes. You don't want to be sitting 24/7 or running 24/7.

Re: Energy-based model explains how chronic stress transforms into disease over time

#27
So what do you do about stress? How do you recognize it's happening? I found this part informative:

"Stress reactivity occurs specifically in situations that diminish one’s control and where the prospect of being negatively evaluated, rejected, and/or shamed are contextually manipulated (Dickerson et al., 2004)."

I find I get the most stressed when I'm excited about a new challenge -- a new work project, seeing a path to achieving a goal I've been working towards for a while. When I start to feel too excited (or in the framework of this paper, I start to expend too much energy and my heart rate is elevated thinking about all I want to do to overcome the challenge), I can generally reign in the stress by reminding myself that failure happens, my peers will understand it, and I don't have complete control over anything anyway.

Re: Energy-based model explains how chronic stress transforms into disease over time

#28
post #11

doesn't matter what model you use to explain it. cortisol. too much of it or too regularly opens the door to many diseases.

Are there any proxy markers we can use to model cortisol, right now? Like HRV or simply continuous heart rate monitoring?

Re: Energy-based model explains how chronic stress transforms into disease over time

#30

Earlier quoted context omitted.

The body tends to use the same amount of energy regardless of what you do in a day. You can certainly over exercise which causes undue stress on the body. However other than an adaptive period at the start of regular exercise your body adapts to the increased caloric use from exercise by down regulating other processes to conserve energy. Typically an excess of calories is used by production of lipid fluid in adipose…

How did you come by this information and do you have any sources / further reading on this?

This is basically exercise physiology 101.

I'm not saying that to be snarky. Just as an FYI that it can be kinda hard to even describe how one came across this knowledge. Like asking someone how they know LC circuits act as a resonator.

And I guess exercise science is even less popular than physics. You can find the latter on Wikipedia, and a bit of the former too:

https://en.m.wikipedia.org/wiki/Exercise_physiology

There is a lot of great YouTube content about exercise physiology too, if you can cut through the "bro science" ecosystem.

Post reply on HN